Thermal processing apparatus for a band film

A thermal processing apparatus comprising:

• a heating unit including a pair of heating bodies for heating a band film conveyed along a predetermined film feeding path defined by a film guide;
• an embossing unit including a punch and a die for forming a predetermined raised pattern on a heated surface of said band film;
• and
• a shifting mechanism for controllably shifting said heating bodies in opposed first and second directions with predetermined strokes during a thermal processing operation, said strokes being so short that said band film may be subjected to an excessive temperature increase when held continuously between said heating bodies without being conveyed along said predetermined film feeding path
• wherein said shifting mechanism shifts said heating bodies in said first and second directions to controllably position said heating bodies adjacent to a surface of said band film to increase the temperature of said surface of the band film to a predetermined value, and shifts said heating bodies in a third direction transverse to said first and second directions to separate said heating bodies from said band film by a distance sufficient to prevent thermal damage when said thermal processing is interrupted or stopped.